He says "pretty much the majority of our Z77 boards". That is not the same as "all". And again, support is not listed on the Sabertooth's specifications page or in the user manual, and it's not listed as an available download for the motherboard.

Now, it might work, but that's likely a coincidence rather than deliberate.

I just finished building my computer today and I can tell you from using the Asus p8z77- v deluxe is like a dream. Simplcity is all that is really needed to describe it. Makes it very easy for a novice user like me.